(1) Field
The present invention relates generally to reverse drives for motorcycles and, more particularly, to portable or removable or after-market devices that allow motorcycles to drive in reverse.
(2) Related Technology
Motorcycle transmissions having a reverse gear are known in the art. Most commonly, however, both new and old motorcycles lack reverse gears. To reverse motorcycles lacking a reverse gear, the rider must walk the motorcycle backwards. This can be very difficult, even dangerous, if the motorcycle is too heavy to for a particular rider to push or if the motorcycle needs to be reversed uphill. Others have recognized the problem.
United States Patent Application Publication 2003/0038437 (“Ungvari”) discloses a portable reverse drive shown in FIG. 1a. Ungvari's drive includes a rigid frame having a lower frame portion 1a and an upper frame portion 1b. Attached to lower frame portion 1a, is a pair of lower rollers 2a mounted on lower axles 3a and secured by lower axle nuts 4a. Attached to upper frame portion 1b is an upper roller 2b mounted on an upper axle 3b. 
FIG. 2 shows Ungvari's drive in use. The drive is placed in front of the rear wheel 7 of a motorcycle. The rider then drives forward, first up onto the drive, and then as power is transmitted to Ungvari's roller 2a′, the motorcycle is propelled backward 6 to the desired location. To get off the drive, the rider disengages the clutch, or shifts the motorcycle into neutral, and rolls backward. Ungvari's upper roller 2b is located toward the front of wheel 7 and is used to keep the motorcycle from advancing forward off the drive or to keep the motorcycle from advancing the drive out from under wheel 7. As a result of this configuration, Ungvari needs a rigid frame 1 to hold roller 2b at the desired height and distance relative to wheel 7. Applicant has discovered various problems with this technique. For example, Ungvari's solution of using upper roller 2b to prevent rearward movement of the drive necessitates a rigid upper frame to hold the upper roller at the desired height relative to wheel 7 and necessitates a rigid lower frame to prevent the forward movement of roller 2b relative to the lower frame. Further, Ungvari's drive only provides a reverse drive force through a single roller, the rearmost lower roller 2a′. Applicant's invention addresses these and additional problems.